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<head>
    <meta charset="UTF-8">
    <title>Title</title>
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<body>
    <script>
 /*2、根据Date对象获取当前的日期和时间，根据不同时间段显示不同的问候语
function greeting(hour){
if(hour < 6){return "凌晨好！"}
else if (hour < 9){return "早上好！";}
else if (hour < 12){return "上午好！";}
else if (hour < 14){return "中午好！";}
else if (hour < 17){return "下午好！";}
else if (hour < 19){return "傍晚好！";}
else if (hour < 22){return "晚上好！";}
else {return "夜里好！";}
}*/
     var date = new Date();
     var hour = date.getHours();
 function greeting(hour) {
     if (hour < 6) {
         return "凌晨好！"
     } else if (hour < 9) {
         return "早上好！";
     } else if (hour < 12) {
         return "上午好！";
     } else if (hour < 14) {
         return "中午好！";
     } else if (hour < 17) {
         return "下午好！";
     } else if (hour < 19) {
         return "傍晚好！";
     } else if (hour < 22) {
         return "晚上好！";
     } else {
         return "夜里好！";
     }
 }
     var greet = greeting(hour);
     alert(greet);
    </script>
</body>
</html>